Inhibition of the activity of poly (ADP‐ribose) polymerase reduces heart ischaemia/reperfusion injury via suppressing JNK‐mediated AIF translocation

Poly (ADP‐ribose) polymerase (PARP) has been proposed to play an important role in the pathogenesis of heart ischaemia/reperfusion (I/R) injury. However, the mechanisms of PARP‐mediated heart I/R injury in vivo are still not thoroughly understood. Therefore, in this study, we investigate the effect of PARP inhibition on heart I/R injury and try to elucidate the underlying mechanisms. Studies were performed with I/R rats' hearts in vivo. Ischaemia followed by reperfusion caused a significant increase in Poly (ADP‐ribose) (PAR), c‐Jun NH2‐terminal kinase (JNK) and apoptosis‐inducing factor (AIF) activity. Administration of 3,4‐dihydro‐5‐[4‐(1‐piperidinyl)butoxy]‐1(2H)‐isoquinolinone (DPQ), an inhibitor of PARP, decreased myocardial infarction size from 61.11±7.46%[0] to 38.83±5.67% (P